The adapter's voltage has to match the factory one (usually 19 V, or 14.85 V in Apple's case), and its power must be the same or higher: 45 W feeds an ordinary laptop, 120–150 W a gaming machine. The third figure, the one most often forgotten, is the plug diameter — 5.5x2.5 mm, for example: it has to physically fit the socket. For travelling there are car adapters too, running off a 12 V socket.
Find accessories for your phone
Select manufacturer and model
The adapter's voltage has to match the factory one (usually 19 V, or 14.85 V in Apple's case), and its power must be the same or higher: 45 W feeds an ordinary laptop, 120–150 W a gaming machine. The third figure, the one most often forgotten, is the plug diameter — 5.5x2.5 mm, for example: it has to physically fit the socket. For travelling there are car adapters too, running off a 12 V socket.